Improvements in the use, method and apparatus for using inflate liner systems for discharging bulk material from storage vessels

ABSTRACT

In a storage container having a floor and a sidewall defining a space for a flowable material, and an inflatable liner attached at a first edge to the side wall along a line spaced from the floor, and attached at an opposite second edge to the floor along a line spaced from the sidewall, the inflatable liner adapted to be inflated to facilitate emptying the flowable material from the storage container, the improvement comprising a retraction system for retracting the liner as it is deflated.

FIELD

The present disclosure relates to improvements in the use, method and apparatus for using inflate liner systems for discharging bulk material from storage vessels.

BACKGROUND

This section provides background information related to the present disclosure which is not necessarily prior art.

This invention relates to improvements for handling, storing, aerating and discharging dry bulk materials, such as feed and grain, from flat-bottom storage and transport vessels such as bins, silos, trucks, barges, ships, rail cars, gran wagons, bunker storage, etc., and in particular to systems and methods for retracting inflatable liners used in such storage and transport vessels.

Since the use of silos with flat-bottom floors and some hopper designs have been used for storing grain for the last hundred plus years, the vast majority use an exposed sweep auger (which can be extremely dangerous) for emptying grain once gravity flow stops. This process usually occurs with one or more workers inside the silo, while the sweep auger is running which is extremely dangerous and is and has been a major safety concern with OSHA. An alternative is to use inflatable liners to facilitate the emptying of the grain, as disclosed in prior published PCT Application WO2017024184 Flexible Liner System For Discharging And Aerating Dry Materials In A Storage Bin, the contents of which are incorporated herein by reference. However one of the more vexing and most difficult problems to solve in larger storage silos (e.g., silos larger than 15′ in diameter is to have the inflatable liner system return to the wall and floor/wall joint of the container so the container can be re-filled. In large silos (e.g., 36′ diameter and 48′ diameter), the inflatable liner(s) typically fell down to the floor and beyond the liner's inflate compartment, crossing the conveyor system in the center of the silo and into the opposing liner's inflate compartment. after complete inflation was reached. As each liner continued to deflate, the fabric would wrinkle, fold and lay on itself in such a manner that a vacuum system could not pull it back. This is exacerbated by the fact that when the liner falls back to the floor, a partial vacuum is often created under the liner that actually helps hold the liner in place so that it cannot be pulled back into position.

SUMMARY

This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.

Embodiments of the present invention provide a gravity based “liner pull back system” that not only pulls the inflatable liner back into position for re-filling, but can do so without controls, power or need for actuation, adding a major reliability factor to the invention. Embodiments of this new system can also be used when aeration tubes are used with the inflate liner system for conditioning grain.

In preferred embodiment, a storage container having a floor and a sidewall defining a space for a flowable material, has an inflatable liner attached at a first edge to the side wall along a line spaced from the floor, and attached at an opposite second edge to the floor along a line spaced from the sidewall. The inflatable liner is adapted to be inflated to facilitate emptying the flowable material from the storage container. In accordance with the principles of this invention, a retraction system is provided for retracting the liner as it is deflated.

The retraction system comprises at least one lower retractor. Each lower retractor comprises a lower anchor secured to the liner at a position intermediate the first and second edges. A lower retractor line engages the lower anchor, and a lower retractor mechanism resiliently pulls the lower retractor line generally downwardly and outwardly toward the corner of the sidewall and floor.

The retraction system further comprises at least one upper retractor. Each upper retractor comprising an upper anchor secured to the liner at a position intermediate the first edge and the lower anchor. An upper retractor line engages the upper anchor, and a lower retractor mechanism resiliently pulls the upper retractor line generally horizontally toward the sidewall, so that as the liner is deflated, the liner is generally pulled outwardly toward the sidewall.

The upper retractor mechanism comprises preferably comprises at least one pulley generally adjacent the sidewall and a counter weight attached to the upper retractor line, to exert a pulling force on the line to draw the upper portion of the liner outwardly toward the sidewall. The upper anchor comprises an upper elongate anchor member disposed on the liner. An end of the upper retractor line is secured to each end of the upper elongate anchor member. the portion of the upper retractor line intermediate the ends extends over two pulleys and has a counter weight secured thereon. The upper anchor preferably comprises an elongate pocket formed on the liner and the elongate anchor member disposed in the elongate pocket.

The lower retractor mechanism preferably comprises a first pulley adjacent the corner between the floor and the sidewall, and a second pulley adjacent the sidewall and spaced from the floor, and a counterweight on the lower retractor line.

The inflatable liner preferably extends along a length of the sidewall, and there are a plurality of upper and lower retractor mechanisms spaced along the length of the liner. The upper and lower retractors are laterally offset from each other.

Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

FIG. 1 is front elevation view of a lift pocket assembly in accordance with the principles of this invention;

FIG. 2 is a side elevation view of the lift pocket assembly;

FIG. 3 is front elevation view of a lift pocket assembly with the inflatable liner wall shown inflated;

FIG. 4 is a side elevation view of the lift pocket assembly with the inflatable liner wall shown inflated;

FIGS. 5 to 14 are sequential cross sectional views of the deflation movement of an inflatable liner with a preferred embodiment of a retraction system in accordance with the principles of this invention;

FIG. 15 is a top view of grain silo 17 showing inflatable liner with a preferred embodiment of a retraction system in accordance with the principles of this invention;

FIGS. 16 to 19 are sequential front views of the operation of a retraction system in accordance with the principles of this invention;

FIG. 20 is a side view of grain silo 17 with aeration tube 98 and a preferred embodiment of a retraction system in accordance with the principles of this invention;

FIG. 21 is an end view concrete silo wall with anchor bolt hole 57B;

FIG. 22 is a side view of inflatable liner that is equipped with bungee spring;

FIG. 23 is an end view of the inflatable liner system used with a preferred embodiment of a retraction in accordance with the principles of this invention;

FIG. 24 is a front view on inflate liner wall showing roped edge assembly with liner cable supports secured;

FIG. 25 is a front view of inflate liner wall equipped with lifting loops;

FIG. 26 is a front view of inflate liner wall placed below liner lift brackets;

FIG. 27 is a top view of a concrete silo elevator installation; and

FIG. 28 is a side view of grain silo with access cover assembly

Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.

DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference to the accompanying drawings.

FIGS. 1 to 4 are views of lift pocket assembly 317 fixed to the backside of inflatable liner wall 38 to create liner reserve 323. FIG. 1 is a front view of lift pocket assembly attached to inflatable liner 38 (not shown), with lift pulleys 320 a and 320 b are attached to top of inflate liner 38 in the area of silo wall clamp bar assembly 31 via pulley mount fixtures 324 a and 324 b respectively. Pulleys 320 a and 320 b may also be secured to silo wall 20. Pulley mount fixtures 3204 a and 324 b may be made of webbing material or PVC coated fabric with a reasonably high tensile strength. Counterweight 321 is attached to lift cable 319 to raise lift pocket assembly 317 and inflate liner wall 38 (not shown) upward when liner 38 is not in the inflation mode.

Ends of lift cable 319 are secured to cable attachments 322 a and 322 b that are equipped on lift pocket assembly 317. Typically, cable attachments can be grommets or another type of heavy-duty fastener. FIG. 2 is a side view of lift pocket assembly 317 attached to inflate liner 38 via heat seal with stiffener 318 placed inside to provide support over varying lengths of lift pocket assembly 317. As shown in the configuration, pulley 320 is fixed to silo wall 20. When the inflation cycle has been completed after full inflation, counterweight 321 will enable lift cable 319 to raise lift pocket assembly 317 and inflate liner 38 to create liner reservoir 323. Conversely, when inflate liner 38 is under inflation and expanding, counterweight 321 will be raised in response to the outward and upward movement of inflate liner 38 during the silo unloading process as shown in FIGS. 3 and 4.

FIGS. 5 to 14 are sequential side views of deflation movement of inflatable liner 38 a from a fully inflated condition to a completely deflated and re-seated condition against the silo floor 22 and the silo wall 20 in left side of grain silo 17. To accomplish the task of completely pulling back inflatable liner 38 a to a “silo re-fill” position, liner reservoir assembly 317 x and liner return assembly 41X function together by putting immediate and constant “pull back” pressure on inflatable liner 38 a. As shown, liner reservoir assembly 317 x is made up of lift pocket assembly 317 (with flexible rod 318 enclosed) secured to inflatable liner 38 a. LP cable 319 is connected to lift pocket assembly 317 on one end with counterweight 321 attached on its other end. Upward force is placed on lift pocket assembly 317 by passing LP cable through LP pulley 320 (secured top of inflatable liner 38 a via liner cable support 324) with counterweight 321 suspended above silo floor 22. For most silo applications, counterweight 321 may weigh between 25 to 50 pounds which is more than enough weight to lift inflate liner 38 a up to create a reservoir of folded inflate liner 38 a as air pressure is reduced to zero inside inflate liner compartment 30 a. Also, as shown, the liner return assembly 41X can comprise liner return cord 41 which in turn is connected to inflate liner 38 a via liner return anchor 43 b and counterweight 43W on the other end. Return cord 41 (which may be steel cable), runs through lower liner pulley 42 c which is located on silo wall 20 and then up to upper liner pulley 42 b which can be attached to silo wall 20 (or top of inflate liner 38 a in a similar manner to how LP pulley 320 is secured to inflate liner 38 a) and then back down to weighted pulley assembly 42 a and back up through upper liner pulley 42 b and finally to liner cord anchor 42 x (not shown) which is secured to silo wall 20. For some installations of liner return assembly 41X that don't require a long stretch of liner cord 41, weight pulley assembly 42 a may be eliminated whereby liner return cord 41 can be connected directly to counterweight 42 z.

In FIG. 6, inflatable liner 38 a has begun the deflation cycle as low pressure air is exhausted from liner air compartment 30 a via liner inflation port 34. Liner inflation port 34 functions as a slight bottle neck to maintain some air pressure inside liner air compartment 30 a so that inflatable liner remains in an elevated and inflated position so that liner cord 41 can pull inflate liner 38 a to silo wall 20 before it is completely deflated. The action of liner return cord 41 placing significant and continuous force on inflatable liner 38 a via counterweight 42 z (typically between 150 to 500 pounds, depending on the size of grain silo 17) helps keep liner inflated at a very low pressure to ensure that inflatable liner 38 a does not fall down onto silo floor 22 and over auger 25; and then dragged across silo floor 22. If inflatable liner 38 a ends up being folded and bunched up on silo floor 22, re-seating of inflate liner 38 a may not be possible. As inflatable liner 38 a is pulled back, counterweights 321 and 43W are functioning properly and working together to achieve the correct procedure for returning inflatable liner 38 a for re-filling of grain 39.

As shown in FIGS. 7 to 11, inflatable liner 38 a continues to be pulled back into a re-fill position. If aeration tube(s) 98 (not shown) are attached to inflate liner 38 a via liner return support 324, counterweights 321 and 43 w may need to be heavier to handle the additional load and weight. In FIGS. 11 to 13 that counterweight 321 and liner return weight 43W are in the lowest and resting positions. Also some air remains between inflatable liner 38 a and silo wall 20 and silo floor 22 as the deflation or pull back cycle is completed. Inflatable liner 38 a is now in the correct position for refilling silo 17 with inflate liner reservoir 38S created and established under clamp bar assembly 31 a and liner cable support 324 pulled tight.

In FIG. 14, air that remains in air compartment 30 a will be further exhausted via liner inflation port 34 c as grain 39 is loaded into grain silo 17. Should any gaps occur between inflate liner 38 a and silo wall 20 which could lead to added stress and possible damage to grain silo 17 and inflate liner 38 a, extra inflatable liner 38 a material from inflatable liner reservoir 38S can be pulled down too fill these or other gaps. The inflate liner reservoir 38S provides extra fabric when needed of inflate liner 38 a to prevent “hammocking” within air liner compartment 30 a. As grain 39 is filled above clamp bar assembly 31 a, virtually any remaining air in air compartment 30 a will be exhausted. In some applications, a small vacuum assist system can be used in conjunction with the liner pull back system.

FIG. 15 is a top view of grain silo 17 showing inflatable liner 38 a positioned on silo floor 22 between conveyor housing 23 and silo wall 20 in a fairly outstretched and taught condition because liner cable supports 324 a to 324 f are applying force on inflate liner 38 a towards silo wall 20 because of liner return weights counterweights 43Wa, 43Wb and 43Wc (not shown) of liner return assemblies 41Xa, 41Xb and 41Xc. Also shown is flared end conveyor trough 23FE adjacent to door 218, to provide added support to inflatable liner 38 a, flexible rods 318 a to 318 f may be used in conjunction will liner supports 324 a to 324 f respectively to spread the load. The liner cable supports are preferably generally spaced apart equally to provide adequate and even pull-back force.

FIGS. 16 to 19 are sequential front views of the operation of liner return assemblies 41Xa, 41Xb and 41Xc and the relationship between the movement and positions of liner return weights 43Wa, 43Wb and 43Wc relative to the movement and positions of liner cable supports 324 a and 324 b; 324 c and 324 c and 324 e and 324 f respectively. Lower liner pulleys 42Ca 42 c 6 may be mounted on silo floor 20 or on the lower silo wall 20 area as shown.

FIG. 20 is a side view of grain silo 17 with aeration tube 98 mounted from aeration tube coupling 98C on conveyor housing 23 b to liner cable support 43 b attached to inflate liner 38F and liner return cord 41. To provide smooth operation of liner cable support assembly 43 b as it near silo floor 22, liner support wheel 42W is attached. When aeration tube(s) 98 are secured too inflate liner 38, counterweight size should be increased because of added load. It is also important to point out that aeration tubes (98) have only two points of attachment, typically at or near both ends. This allows the aeration tubes (98) to twist, turn, bend and move as the inflate liner 38 moves during inflation and deflation. The movement and twisting action of the aeration tubes helps reduce the amount of grain that might get trapped between the inflate liner 38 and aeration tubes.

FIG. 21 is an end view concrete silo wall with anchor bolt hole 57B drilled out so that anchor bolt 57 a may be inserted. For most applications, a Hilti™ type anchor should be used because it is more secure with its chemical adhesive bond to the concrete. As shown, a heavy duty, compressible sealant material can be used between clamp bar mounting plate 54 and silo wall 20. Flexible shield 64 that extends from roped edge area of inflatable liner can also be adhered to the silo wall via a sealant. The use of sealants will provide an air tight connection in the area of the clamp bar mounting plate 54 and clap bar 56.

FIG. 22 is a side view of inflatable liner 38 that is equipped with bungee spring 211 connected to bungee anchor 216 b mounted on silo floor 22 and bungee anchor 216 a secured to inflatable liner 38. During the final inflation sequence, of inflate liner 38, bungee spring will stretch out under tension so that when the deflation cycle begins and inflate liner 38 begins to be pulled back into place for refilling, bungee spring 211 will apply force to inflate liner near conveyor trough to pull inflate liner 38 back towards silo wall (not shown) to reduce wrinkling and folding of the inflatable liner.

FIG. 23 is an end view of the inflatable liner system 38 a used with the liner return assembly 41X and liner reservoir assembly 317X in a rectangular shape container such as a hold on a ship or barge, highway trailer compartment, railroad box car, etc. . . . For example, FIG. 23 could be that of a double walled barge.

FIG. 24 is a front view on inflate liner wall 85 showing roped edge assembly 79 with liner cable supports 324 a to 324 x secured. Liner cable supports 324 a to 324 x can also be secured directly to silo wall (not shown) or clamp bar assembly (not shown). Also shown are liner folds that form liner pleats 78 a to 78 k along the roped edge area of inflate liner wall 85 that may be located in between lift pocket assemblies 371 a to 317L respectively. One method to provide liner reservoir reserve 80 is to locate it at the bottom of inflate liner 85. To protect inflate liner 85 from the pulleys and cables used with liner cable supports 324 a to 324 x in conjunction with lift pocket assemblies 317 a to 317L, protective guards made of heavy-duty flexible material be secured to roped edge 79 and or liner cable supports between inflate liner wall 85.

FIG. 25 is a front view of inflate liner wall 85 equipped with lifting loops 344 a to 344 f to provide a point of attachment to raise liner up to the clamp bar location on silo wall (not shown) for installation. A rope secured to a C-Clamp or other device may also work.

FIG. 26 is a front view of inflate liner wall 85 placed below liner lift brackets 90 a to 90 f secured to silo wall to provide a secure lifting location above clamp bar assembly (not shown) to lift and hold inflate liner 85 during the installation process. Typically, a rope can be used that can be run through lifting loop bracket(s) 90 with or without a pulley to lift inflate wall liner 85.

FIG. 27 is a top view of a concrete silo elevator installation showing silos 17 a to 17 d equipped with a side-discharge outlets 345 a to 345 d respectively. Discharge chutes 346 a to 346 d are connected to discharge outlets 345 a to 345 d respectively to direct flow of grain via gravity from inside silo to belt conveyor 347 located underneath the floors of silos 17 a to 17 d. So that installation of the inflate liners 85 a and 85 b (not shown) and conveyor housing 23 (not shown) can be performed inside silos 17 a to 17 d, access openings 348 a to 348 f are made into silo walls of silos 17 a to 17 d respectively.

FIG. 28 is a side view of grain silo 17 with access cover assembly 348 made in silo wall 20 a. Also shown are access cover 349 with inflate liner conduit 350 and aeration conduit 351 secured to provide inflation and aeration operation inside silo 17. As part of the inflate liner system, conveyor housing 23 is placed on silo floor 22. Power cords and other instrumentation devices may also be located on/through access cover 349.

In the spirit of the invention, it is anticipated that various combinations of conveyors, inflate liners, silo shapes/hoppers and aeration equipment (using only an outer liner or both an inner and outer liner), may be used in various configurations with one another as shown in this provisional application.

The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.

The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure. 

What is claimed is:
 1. In a storage container having a floor and a sidewall defining a space for a flowable material, and an inflatable liner attached at a first edge to the side wall along a line spaced from the floor, and attached at an opposite second edge to the floor along a line spaced from the sidewall, the inflatable liner adapted to be inflated to facilitate emptying the flowable material from the storage container, the improvement comprising a retraction system for retracting the liner as it is deflated, the retraction system comprising at least one lower retractor, each lower retractor comprising a lower anchor secured to the liner at a position intermediate the first and second edges, a lower retractor line engaging the lower anchor, and a lower retractor mechanism for resiliently pulling the lower retractor line generally downwardly and outwardly toward the corner of the sidewall and floor; and at least one upper retractor, each upper retractor comprising an upper anchor secured to the liner at a position intermediate the the first edge and the lower anchor, an upper retractor line engaging the upper anchor, and a lower retractor mechanism for resiliently pulling the upper retractor line generally horizontally toward the sidewall, so that as the liner is deflated, the liner is generally pulled outwardly toward the sidewall.
 2. The improved storage container according to claim 1 wherein the upper retractor mechanism comprises at least one pulley generally adjacent the sidewall and a counter weight attached to the upper retractor line.
 3. The improved storage container according to claim 2 wherein the inflatable liner extends along a length of the sidewall, and wherein there are a plurality of upper and lower retractor mechanisms spaced along the length of the liner.
 4. The improved storage container according to claim 1 wherein the upper anchor comprises an elongate pocket formed on the liner and an elongate anchor member disposed in the elongate pocket.
 5. The improved storage container according to claim 1 wherein the upper anchor comprises an upper elongate anchor member disposed on the liner.
 6. The improved storage container according to claim 5 wherein an end of the upper retractor line is secured to each end of the upper elongate anchor member.
 7. The improved storage container according to claim 6 wherein the portion of the upper retractor line intermediate the ends extends over two pulleys and has a counter weight secured thereon.
 8. The improved storage container according to claim 7 further comprising an elongate pocket on the liner for engaging the upper elongate anchor member.
 9. The improved storage container according to claim 1 wherein there are a plurality of upper and lower retractors and wherein the upper and lower retractors are laterally offset from each other.
 10. The improved storage container according to claim 1 wherein the lower retractor mechanism comprises a first pulley adjacent the corner between the floor and the sidewall, and a second pulley adjacent the sidewall and spaced from the floor, and a counterweight on the lower retractor line.
 11. In an inflatable liner of the type adapted to be installed in a storage container with a first edge secured to the wall of the storage container along a line spaced from the floor, and a second edge attached to the floor along a line spaced from the wall, so that the liner can be inflated to facilitate emptying flowable material from the storage container, the improvement comprising a retraction system for retracting the liner as it is deflated, the retraction system comprising at least one lower retractor, each lower retractor comprising a lower anchor secured to the liner at a position intermediate the first and second edges, a lower retractor line engaging the lower anchor, and a lower retractor mechanism for resiliently pulling the lower retractor line generally downwardly and outwardly toward the corner of the sidewall and floor; and at least one upper retractor, each upper retractor comprising an upper anchor secured to the liner at a position intermediate the the first edge and the lower anchor, an upper retractor line engaging the upper anchor, and a lower retractor mechanism for resiliently pulling the upper retractor line generally horizontally toward the sidewall, so that as the liner is deflated, the liner is generally pulled outwardly toward the sidewall. 